<?php

/**

 * Zend Framework

 *

 * LICENSE

 *

 * This source file is subject to the new BSD license that is bundled

 * with this package in the file LICENSE.txt.

 * It is also available through the world-wide-web at this URL:

 * http://framework.zend.com/license/new-bsd

 * If you did not receive a copy of the license and are unable to

 * obtain it through the world-wide-web, please send an email

 * to license@zend.com so we can send you a copy immediately.

 *

 * @category   Zend

 * @package    Zend_Mail

 * @subpackage Protocol

 * @license    http://framework.zend.com/license/new-bsd     New BSD License

 */

/**

 * @category   Zend

 * @package    Zend_Mail

 * @subpackage Protocol

 * @license    http://framework.zend.com/license/new-bsd     New BSD License

 */

class Zend_Mail_Protocol_Pop3

{

    /**

     * Default timeout in seconds for initiating session

     */

    const TIMEOUT_CONNECTION = 30;

    /**

     * saves if server supports top

     * @var null|bool

     */

    public $hasTop = null;

    /**

     * socket to pop3

     * @var null|resource

     */

    protected $_socket;

    /**

     * greeting timestamp for apop

     * @var null|string

     */

    protected $_timestamp;

    /**

     * Public constructor

     *

     * @param  string      $host  hostname or IP address of POP3 server, if given connect() is called

     * @param  int|null    $port  port of POP3 server, null for default (110 or 995 for ssl)

     * @param  bool|string $ssl   use ssl? 'SSL', 'TLS' or false

     * @throws Zend_Mail_Protocol_Exception

     */

    public function __construct($host = '', $port = null, $ssl = false)

    {

        if ($host) {

            $this->connect($host, $port, $ssl);

        }

    }

    /**

     * Public destructor

     */

    public function __destruct()

    {

        $this->logout();

    }

    /**

     * Open connection to POP3 server

     *

     * @param  string      $host  hostname or IP address of POP3 server

     * @param  int|null    $port  of POP3 server, default is 110 (995 for ssl)

     * @param  string|bool $ssl   use 'SSL', 'TLS' or false

     * @return string welcome message

     * @throws Zend_Mail_Protocol_Exception

     */

    public function connect($host, $port = null, $ssl = false)

    {

        if ($ssl == 'SSL') {

            $host = 'ssl://' . $host;

        }

        if ($port === null) {

            $port = $ssl == 'SSL' ? 995 : 110;

        }

        $errno  =  0;

        $errstr = '';

        $this->_socket = @fsockopen($host, $port, $errno, $errstr, self::TIMEOUT_CONNECTION);

        if (!$this->_socket) {

            /**

             * @see Zend_Mail_Protocol_Exception

             */

            require_once 'Zend/Mail/Protocol/Exception.php';

            throw new Zend_Mail_Protocol_Exception('cannot connect to host; error = ' . $errstr .

                                                   ' (errno = ' . $errno . ' )');

        }

        $welcome = $this->readResponse();

        strtok($welcome, '<');

        $this->_timestamp = strtok('>');

        if (!strpos($this->_timestamp, '@')) {

            $this->_timestamp = null;

        } else {

            $this->_timestamp = '<' . $this->_timestamp . '>';

        }

        if ($ssl === 'TLS') {

            $this->request('STLS');

            $result = stream_socket_enable_crypto($this->_socket, true, STREAM_CRYPTO_METHOD_TLS_CLIENT);

            if (!$result) {

                /**

                 * @see Zend_Mail_Protocol_Exception

                 */

                require_once 'Zend/Mail/Protocol/Exception.php';

                throw new Zend_Mail_Protocol_Exception('cannot enable TLS');

            }

        }

        return $welcome;

    }

    /**

     * Send a request

     *

     * @param string $request your request without newline

     * @return null

     * @throws Zend_Mail_Protocol_Exception

     */

    public function sendRequest($request)

    {

        $result = @fputs($this->_socket, $request . "\r\n");

        if (!$result) {

            /**

             * @see Zend_Mail_Protocol_Exception

             */

            require_once 'Zend/Mail/Protocol/Exception.php';

            throw new Zend_Mail_Protocol_Exception('send failed - connection closed?');

        }

    }

    /**

     * read a response

     *

     * @param  boolean $multiline response has multiple lines and should be read until "<nl>.<nl>"

     * @return string response

     * @throws Zend_Mail_Protocol_Exception

     */

    public function readResponse($multiline = false)

    {

        $result = @fgets($this->_socket);

        if (!is_string($result)) {

            /**

             * @see Zend_Mail_Protocol_Exception

             */

            require_once 'Zend/Mail/Protocol/Exception.php';

            throw new Zend_Mail_Protocol_Exception('read failed - connection closed?');

        }

        $result = trim($result);

        if (strpos($result, ' ')) {

            list($status, $message) = explode(' ', $result, 2);

        } else {

            $status = $result;

            $message = '';

        }

        if ($status != '+OK') {

            /**

             * @see Zend_Mail_Protocol_Exception

             */

            require_once 'Zend/Mail/Protocol/Exception.php';

            throw new Zend_Mail_Protocol_Exception('last request failed');

        }

        if ($multiline) {

            $message = '';

            $line = fgets($this->_socket);

            while ($line && rtrim($line, "\r\n") != '.') {

                if ($line[0] == '.') {

                    $line = substr($line, 1);

                }

                $message .= $line;

                $line = fgets($this->_socket);

            };

        }

        return $message;

    }

    /**

     * Send request and get resposne

     *

     * @see sendRequest(), readResponse()

     *

     * @param  string $request    request

     * @param  bool   $multiline  multiline response?

     * @return string             result from readResponse()

     * @throws Zend_Mail_Protocol_Exception

     */

    public function request($request, $multiline = false)

    {

        $this->sendRequest($request);

        return $this->readResponse($multiline);

    }

    /**

     * End communication with POP3 server (also closes socket)

     *

     * @return null

     */

    public function logout()

    {

        if (!$this->_socket) {

            return;

        }

        try {

            $this->request('QUIT');

        } catch (Zend_Mail_Protocol_Exception $e) {

            // ignore error - we're closing the socket anyway

        }

        fclose($this->_socket);

        $this->_socket = null;

    }

    /**

     * Get capabilities from POP3 server

     *

     * @return array list of capabilities

     * @throws Zend_Mail_Protocol_Exception

     */

    public function capa()

    {

        $result = $this->request('CAPA', true);

        return explode("\n", $result);

    }

    /**

     * Login to POP3 server. Can use APOP

     *

     * @param  string $user      username

     * @param  string $password  password

     * @param  bool   $try_apop  should APOP be tried?

     * @return void

     * @throws Zend_Mail_Protocol_Exception

     */

    public function login($user, $password, $tryApop = true)

    {

        if ($tryApop && $this->_timestamp) {

            try {

                $this->request("APOP $user " . md5($this->_timestamp . $password));

                return;

            } catch (Zend_Mail_Protocol_Exception $e) {

                // ignore

            }

        }

        $result = $this->request("USER $user");

        $result = $this->request("PASS $password");

    }

    /**

     * Make STAT call for message count and size sum

     *

     * @param  int $messages  out parameter with count of messages

     * @param  int $octets    out parameter with size in octects of messages

     * @return void

     * @throws Zend_Mail_Protocol_Exception

     */

    public function status(&$messages, &$octets)

    {

        $messages = 0;

        $octets = 0;

        $result = $this->request('STAT');

        list($messages, $octets) = explode(' ', $result);

    }

    /**

     * Make LIST call for size of message(s)

     *

     * @param  int|null $msgno number of message, null for all

     * @return int|array size of given message or list with array(num => size)

     * @throws Zend_Mail_Protocol_Exception

     */

    public function getList($msgno = null)

    {

        if ($msgno !== null) {

            $result = $this->request("LIST $msgno");

            list(, $result) = explode(' ', $result);

            return (int)$result;

        }

        $result = $this->request('LIST', true);

        $messages = array();

        $line = strtok($result, "\n");

        while ($line) {

            list($no, $size) = explode(' ', trim($line));

            $messages[(int)$no] = (int)$size;

            $line = strtok("\n");

        }

        return $messages;

    }

    /**

     * Make UIDL call for getting a uniqueid

     *

     * @param  int|null $msgno number of message, null for all

     * @return string|array uniqueid of message or list with array(num => uniqueid)

     * @throws Zend_Mail_Protocol_Exception

     */

    public function uniqueid($msgno = null)

    {

        if ($msgno !== null) {

            $result = $this->request("UIDL $msgno");

            list(, $result) = explode(' ', $result);

            return $result;

        }

        $result = $this->request('UIDL', true);

        $result = explode("\n", $result);

        $messages = array();

        foreach ($result as $line) {

            if (!$line) {

                continue;

            }

            list($no, $id) = explode(' ', trim($line), 2);

            $messages[(int)$no] = $id;

        }

        return $messages;

    }

    /**

     * Make TOP call for getting headers and maybe some body lines

     * This method also sets hasTop - before it it's not known if top is supported

     *

     * The fallback makes normale RETR call, which retrieves the whole message. Additional

     * lines are not removed.

     *

     * @param  int  $msgno    number of message

     * @param  int  $lines    number of wanted body lines (empty line is inserted after header lines)

     * @param  bool $fallback fallback with full retrieve if top is not supported

     * @return string message headers with wanted body lines

     * @throws Zend_Mail_Protocol_Exception

     */

    public function top($msgno, $lines = 0, $fallback = false)

    {

        if ($this->hasTop === false) {

            if ($fallback) {

                return $this->retrieve($msgno);

            } else {

                /**

                 * @see Zend_Mail_Protocol_Exception

                 */

                require_once 'Zend/Mail/Protocol/Exception.php';

                throw new Zend_Mail_Protocol_Exception('top not supported and no fallback wanted');

            }

        }

        $this->hasTop = true;

        $lines = (!$lines || $lines < 1) ? 0 : (int)$lines;

        try {

            $result = $this->request("TOP $msgno $lines", true);

        } catch (Zend_Mail_Protocol_Exception $e) {

            $this->hasTop = false;

            if ($fallback) {

                $result = $this->retrieve($msgno);

            } else {

                throw $e;

            }

        }

        return $result;

    }

    /**

     * Make a RETR call for retrieving a full message with headers and body

     *

     * @deprecated since 1.1.0; this method has a typo - please use retrieve()

     * @param  int $msgno  message number

     * @return string message

     * @throws Zend_Mail_Protocol_Exception

     */

    public function retrive($msgno)

    {

        return $this->retrieve($msgno);

    }

    /**

     * Make a RETR call for retrieving a full message with headers and body

     *

     * @param  int $msgno  message number

     * @return string message

     * @throws Zend_Mail_Protocol_Exception

     */

    public function retrieve($msgno)

    {

        $result = $this->request("RETR $msgno", true);

        return $result;

    }

    /**

     * Make a NOOP call, maybe needed for keeping the server happy

     *

     * @return null

     * @throws Zend_Mail_Protocol_Exception

     */

    public function noop()

    {